There are two good websites that provide information about roads, traffic, and their many attributes. One is provided by the Illinois Department of Transportation (IDOT) called Getting Around Illinois (GAI). The second is the Traffic Count Database System (TCDS).

Both provide Average Daily Traffic (ADT) counts with TCDS making the information easier to find and presents more of it.

The GAI map has an important layer: jurisdiction. With that information you can determine who has “ownership” of a road. Jurisdiction has been an important factor in the nearly year-long delay of the Jackson Boulevard protected bike lane segment from Ogden Avenue to Halsted Street. IDOT has jurisdiction over this segment (which continues east to Lake Shore Drive; the road is also known as Route 66) and is requiring that the Chicago Department of Transportation do more analysis and revise their designs.

If you are looking for ADT counts, I highly recommend TCDS as it uses the more familiar Google Maps and doesn’t require the Microsoft Silverlight plugin (which is slow and often denigrated with poor usability applications).